var change_date = function(days) {
	// 参数表示在当前日期下要增加的天数
	var now = new Date();
	// + 1 代表日期加，- 1代表日期减
	now.setDate(now.getDate()  + 1 * days);
	var year = now.getFullYear();
	var month = now.getMonth() + 1;
	var day = now.getDate();
	if (month < 10) {
		month = '0' + month;
	}
	if (day < 10) {
		day = '0' + day;
	}

	return  month + '月' + day + '日';
};

